class_docstr: Test MSU GS/A L1B Reader.
class_docstr_tok: ["Test","MSU","GS\/A","L1B","Reader","."]
docstr: Test retrieval in brightness temperature.
docstr_tok: ["Test","retrieval","in","brightness","temperature","."]
code: def test_irbt(self):
      """Test retrieval in brightness temperature."""
      ds_ids = [
          make_dataid(name="C09", calibration="brightness_temperature")
      ]
      res = self.reader.load(ds_ids)
      assert "C09" in res
      assert res["C09"].attrs["calibration"] == "brightness_temperature"
      assert res["C09"].attrs["platform_name"] == "Arctica-M-N1"
      assert res["C09"].attrs["sat_latitude"] == 71.25
      assert res["C09"].attrs["sat_longitude"] == 21.44
      assert res["C09"].attrs["sat_altitude"] == 38500.0
      assert res["C09"].attrs["resolution"] == 4000
  
file_path: satpy/satpy/tests/reader_tests/test_msu_gsa_l1b.py
imports: import os
  from unittest import mock
  import dask.array
  import numpy
  import pytest
  import xarray
  from satpy.tests.reader_tests.test_hdf5_utils import FakeHDF5FileHandler
  from satpy.tests.utils import make_dataid
label_desc: Use image node_id 3 for calling the TestMSUGSABReader obj's underlying member method code with example usage: obj.test_irbt() without return types